Supplements for high-altitude travelers

The altitude-traveler stack — rationale by ingredient

Iron repletion (if ferritin is low) — start 6–8 weeks before departure

Hypoxic adaptation involves increased erythropoietin and red-cell production; iron-deficient travelers acclimatise worse and report more AMS symptoms. Check ferritin 6–8 weeks before a high-altitude trip; aim for a ferritin >30 ng/mL (some experts suggest >50 ng/mL for serious altitude objectives). Use ferrous bisglycinate (gentle iron) 25–50 mg elemental every other day for better absorption and tolerability than daily dosing.

Vitamin D3 to a 25-OH-D of 30–50 ng/mL

Foundational immune and muscle support. Particularly relevant in winter mountain travel from low-sun-exposure baselines.

Electrolyte complex (Na/K/Mg) at altitude

Altitude diuresis is real — increased urine output is part of the acclimatisation response and dehydration accelerates AMS. Pair fluid intake with electrolyte replacement, especially during exertion. Sodium-containing oral rehydration is better than plain water for active days.

Low-dose melatonin 0.3–1 mg before bed

Sleep is reliably disrupted at altitude. Low-dose melatonin (not the 5–10 mg consumer doses) is the best-evidenced sleep adjunct. Avoid the high-dose products — they sediment but don't improve circadian alignment and can produce next-day grogginess on summit days.

Rhodiola rosea — try if you're curious, but don't rely on it

The small AMS-prevention trial base is mixed. Reasonable to add at the standard 200–400 mg/day SHR-5 extract starting 1 week before ascent. Do not substitute for acetazolamide in high-risk profiles.